Guys,
I've read Randy's care and feeding article about the amount of oil in our fuel. In it he indicates that for iron p/c could be 25 -50 % Syn oil. My question is what is the minimum % by volume of Syn oil needed to keep the old iron p/c clean. I have run 75% C / 25% Syn in fuel with 28% total oil but I know the Fox likes castor. Mine are clean inside but was wondering if a lower % of the syn would be better and still keep them from varnishing up.
Best, DennisT